Floquet engineering bulk odd-frequency superconducting pairs

TL;DR

This paper introduces Floquet odd-frequency superconducting pairs, showing they emerge in time-periodic superconductors due to Floquet modes providing an additional symmetry index, opening new avenues for dynamical superconducting states.

Contribution

It establishes the existence of Floquet odd-frequency pairs in periodically driven superconductors, expanding the classification of pair symmetries beyond static systems.

Findings

Floquet modes enable new pair symmetry classifications.

Odd-frequency pairs can be engineered via Floquet driving.

The work suggests new routes for dynamical superconducting states.

Abstract

We introduce the concept of Floquet odd-frequency superconducting pairs and establish their emergence in time-periodic conventional superconductors, where the continuous time-translation invariance is broken. We show that these exotic Cooper pairs are possible because the Floquet modes in time-periodic systems provide an additional index (a Floquet index) that broadens the classification of pair symmetries, with no analog in the static regime. Our results thus put forward a different route for odd-frequency superconducting pairs and pave the way for Floquet engineered dynamical superconducting states.